title: Broad-gain (Δλ/λ0</~0.4), temperature-insensitive (T<0~510K) quantum cascade lasers.
abstract: Broad-gain operation of λ~8.7 μm quantum cascade lasers based on dual-upper-state to multiple-lower-state transition design is reported. The devices exhibit surprisingly wide (~500 cm(-1)) electroluminescence spectra which are very insensitive to voltage and temperature changes above room temperature. With recourse to the temperature-insensitivity of electroluminescence spectra, the lasers demonstrate an extremely-weak temperature-dependence of laser performances: T0-value of 510 K, associated with a room temperature threshold current density of 2.6 kA/cm2. In addition, despite such wide gain spectra, room temperature, continuous wave operation of the laser with buried hetero structure is achieved.
authors.affiliation: Central Research Labs, Hamamatsu Photonics KK, 5000 Hirakuchi, Hamakita-ku, Hamamatsu 434-8601, Japan. kfujita@crl.hpk.co.jp
authors.forename: Kazuue
authors.initials: K
authors.lastname: Fujita
authors.forename: Shinichi
authors.initials: S
authors.lastname: Furuta
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Dougakiuchi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sugiyama
authors.forename: Tadataka
authors.initials: T
authors.lastname: Edamura
authors.forename: Masamichi
authors.initials: M
authors.lastname: Yamanishi
mesh_terms: D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007834:Lasers